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Full-Text Articles in Engineering

Przebieg Zmienności Stężeń Wybranych Zanieczyszczeń W Gazach Odlotowych Z Procesu Mokrego Gaszenia Koksu, Marian Mazur, Robert Oleniacz, Marek Bogacki Dec 2002

Przebieg Zmienności Stężeń Wybranych Zanieczyszczeń W Gazach Odlotowych Z Procesu Mokrego Gaszenia Koksu, Marian Mazur, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

Continuous measurement results of selected constituent concentrations in the gases emitted to the air during the coke wet quenching process were presented and discussed in the paper. The measurements were carried out for the standard wet quenching tower. The research covered such substances as carbon dioxide, carbon monoxide, hydrogen sulfide, nitrogen oxide, nitrogen dioxide and a total content of hydrocarbons and hydrogen (combustible gases). Changeability of the substance concentrations depending of the quenching process duration was analyzed. Among other things the beginning of these substances formation, appearance of the maximum and the range of observed concentrations were taken into consideration. …


Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada Dec 2002

Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada

Otto Vogl

No abstract provided.


Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl Dec 2002

Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl

Otto Vogl

A compilation of articles with short biographies of the scientists who played leading roles in the field and provided the basis of Polymer Science and Technology throughout the 20th century.


Applications Of Underground Structures For The Protection Of Critical Infrastructure, George H. Baker, Richard G. Little, Don A. Linger Nov 2002

Applications Of Underground Structures For The Protection Of Critical Infrastructure, George H. Baker, Richard G. Little, Don A. Linger

George H Baker

The U.S. President’s Commission on Critical Infrastructure Protection (PCCIP), convened in the wake of the bombing of the Murrah Federal Building in Oklahoma City, concluded that the nation’s physical security and economic security depend on our critical energy, communications, and computer infrastructures. While a primary motivating event for the establishment of the commission was the catastrophic physical attack of the Murrah Building, it is ironic that the commission focused its attention primarily on cyber threats. Their rationale was that cyber vulnerabilities posed a new, unaddressed challenge to infrastructure security. This approach was further questioned by the events of September 11, …


Supervisory Control And Data Acquisition (Scada) Systems, George H. Baker, Allan Berg Nov 2002

Supervisory Control And Data Acquisition (Scada) Systems, George H. Baker, Allan Berg

George H Baker

Our critical national infrastructure systems have become almost universally dependent upon computer-based control systems technically referred to as supervisory control and data acquisition (SCADA) systems. SCADA systems evolved from the telemetry and event-alarm systems developed in the early days of utilities. With the widespread use of SCADA systems, computers have become the "basis element" for much of our critical infrastructure. Thus, the disruption of controlling computer terminals and networks due to natural disasters, electric power failure, accidents or malicious activity can have catastrophic consequences.


1. Yukio Imanishi, Otto Vogl Nov 2002

1. Yukio Imanishi, Otto Vogl

Otto Vogl

No abstract provided.


Likwidacja Strefy Ochronnej Huty Katowice I Zakładów Koksowniczych "Przyjaźń" W Dąbrowie Górniczej, Marian Mazur, Robert Oleniacz, Marek Bogacki Oct 2002

Likwidacja Strefy Ochronnej Huty Katowice I Zakładów Koksowniczych "Przyjaźń" W Dąbrowie Górniczej, Marian Mazur, Robert Oleniacz, Marek Bogacki

Robert Oleniacz

Legislation changes in Poland concerning the protective zones (created around industrial plants particularly harmful to the environment) were presented in the paper. Conditions connected with forming, developing and partial elimination of the protective zone existing around the "Katowice" steelworks and the coke plant Przyjaźń in Dąbrowa Górnicza (Poland) since 1978 were characterized as well.

English title: Elimination of the protective zone of the Katowice steelworks and the coke plant Przyjaźń in Dąbrowa Górnicza.


2. Toshinobu Higashimura, Otto Vogl Oct 2002

2. Toshinobu Higashimura, Otto Vogl

Otto Vogl

No abstract provided.


3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder Sep 2002

3. Otto Vogl, Gerald S. Kirshenbaum, Helga Roder

Otto Vogl

No abstract provided.


Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins Aug 2002

Maximization Of The Open Circuit Voltage For Hydrogenated Amorphous Silicon N–I–P Solar Cells By Incorporation Of Protocrystalline Silicon P-Type Layers, R. J. Koval, Chi Chen, G. M. Ferreira, A. S. Ferlauto, Joshua M. Pearce, P. I. Rovira, C. R. Wronski, R. W. Collins

Joshua M. Pearce

In studies of hydrogenated amorphous silicon(a-Si:H) n–i–psolar cells fabricated by rf plasma-enhanced chemical vapor deposition (PECVD), we have found that the maximum open circuit voltage (Voc) is obtained by incorporating p-type doped Si:H layers that are protocrystalline in nature. Specifically, these optimum p layers are prepared by PECVD in the a-Si:H growth regime using the maximum hydrogen-to-silane flow ratio possible without crossing the thickness-dependent transition into the mixed-phase (amorphous+microcrystalline) growth regime for the ∼200 Å p-layer thickness. The strong dependence of the p-layer phase and solar cell Voc on the underlying i-layer phase also confirms the protocrystalline nature of the …


Magnetochemical Origin For Invar Anomalies In Iron-Nickel Alloys, V. Crisan, P. Entel, H. Ebert, H. Akai, Duane D. Johnson, J. B. Staunton Jul 2002

Magnetochemical Origin For Invar Anomalies In Iron-Nickel Alloys, V. Crisan, P. Entel, H. Ebert, H. Akai, Duane D. Johnson, J. B. Staunton

Duane D. Johnson

Zero- and finite-temperature (T) first-principles calculations versus composition (c) show that magnetochemical effects lead to Invar anomalies in Fe-(Ni, Co, Pt) alloys. Chemical short- or long-range order and negative interatomic exchange interaction of electrons in antibonding majority-spin states force the face-centered-cubic lattice to compete simultaneously for a smaller volume (from antiferromagnetic tendencies) and a larger volume (from Stoner ferromagnetic tendencies). The resulting additional negative lattice anharmonicity is very large for Fe-(Ni, Co) while absent for Fe-Pt. Our results explain the T- and c-dependent behavior of Invar properties, including the lattice softening and thermal expansion of Fe-Ni. In addition, the occurrence …


Weryfikacja Emisji Pyłowej Z Huty Katowice I Zasięgu Jej Oddziaływania, Marian Mazur, Robert Oleniacz, Marek Bogacki, Agnieszka Łopata Jun 2002

Weryfikacja Emisji Pyłowej Z Huty Katowice I Zasięgu Jej Oddziaływania, Marian Mazur, Robert Oleniacz, Marek Bogacki, Agnieszka Łopata

Robert Oleniacz

Preliminary analysis of the results of atmospheric dispersion modeling for dust emission from the Katowice Steelworks (Poland) showed necessity of verification the particulate matter, lead and cadmium emission from the plant. The verification was limited to the substance emission sources influencing air pollution to the largest extent. Both scale of dust emission and its granulometric and chemical composition were re-evaluated. Further calculations of the air propagation for the pollutants were carried out and calculation results were compared with direct measurements. Thus the Katowice Steelworks impact on air quality and the level of total dust, lead and cadmium ground deposition was …


Wpływ Związków Metali Alkalicznych W Procesie Spiekania Rud Na Emisję Pyłów, Marian Mazur, Marek Bogacki, Robert Oleniacz Jun 2002

Wpływ Związków Metali Alkalicznych W Procesie Spiekania Rud Na Emisję Pyłów, Marian Mazur, Marek Bogacki, Robert Oleniacz

Robert Oleniacz

The work shows the impact of alkali metals in the sintering process on effectiveness of the electrostatic precipitator and dust emissions into the air. The results of analysis of the content of Na and K in dust discharged from the sinter strand and emitted to the air are presented. It was found that this content is subject to large fluctuations and significantly increases in the dust phase after electrostatic precipitators. Using the balance sheet data, the effect of loads of Na2O and K2O compounds contributed to the sinter mix on emissions of dust. It was also observed high variability of …


Statistical Properties Of Composite Distortions In Hfc Systems And Their Effects On Digital Channels, Ron D. Katznelson May 2002

Statistical Properties Of Composite Distortions In Hfc Systems And Their Effects On Digital Channels, Ron D. Katznelson

Ron D. Katznelson

The statistical properties of Composite Triple Beat (CTB) and Composite Second Order (CSO) distortion terms associated with the analog channels carried on Hybrid Fiber Coax (HFC) are presented. Both simulation and measurement results show that such distortion components falling on individual channels have amplitude Probability Density Function that is nearly Rayleigh distributed (having a Standard Deviation of 5.7 dB). It is shown that both CTB and CSO components have peak envelope power fluctuations that exceed their average (measured) power levels by more than 15 dB. The temporal statistical properties of these distortion components demonstrate peak envelope power fluctuations with characteristic …


Photovoltaics — A Path To Sustainable Futures, Joshua M. Pearce Apr 2002

Photovoltaics — A Path To Sustainable Futures, Joshua M. Pearce

Joshua M. Pearce

As both population and energy use per capita increase, modern society is approaching physical limits to its continued fossil fuel consumption. The immediate limits are set by the planet’s ability to adapt to a changing atmospheric chemical composition, not the availability of resources. In order for a future society to be sustainable while operating at or above our current standard of living a shift away from carbon based energy sources must occur. An overview of the current state of active solar (photovoltaic, PV) energy technology is provided here to outline a partial solution for the environmental problems caused by accelerating …


Absolute Tin(111) Step Energies From Analysis Of Anisotropic Island Shape Fluctuations, S. Kodambaka, V. Petrova, S. V. Khare, Duane D. Johnson, I. Petrov, J. E. Greene Apr 2002

Absolute Tin(111) Step Energies From Analysis Of Anisotropic Island Shape Fluctuations, S. Kodambaka, V. Petrova, S. V. Khare, Duane D. Johnson, I. Petrov, J. E. Greene

Duane D. Johnson

In situ high-temperature (1165–1248 K) scanning tunneling microscopy was used to measure fluctuations around the equilibrium shape of two-dimensional vacancy islands on TiN(111) terraces. From the equilibrium shape, the ratio of the two ⟨110⟩ step energies was found to be 0.72±0.02. Combining this with the results of an exact approach for analysis of shape fluctuations, applicable to highly anisotropic islands, we obtain absolute values for step energies and step stiffnesses as a function of orientation.


Modeling Vegetative Filter Performance With Vfsmod, Matthew J. Helmers, Dean E. Eisenhauer, Michael G. Dosskey, Thomas G. Franti Apr 2002

Modeling Vegetative Filter Performance With Vfsmod, Matthew J. Helmers, Dean E. Eisenhauer, Michael G. Dosskey, Thomas G. Franti

Matthew J. Helmers

The model VFSMOD was used to investigate the effect of varying watershed characteristics and buffer dimensions on the sediment trapping efficiency of vegetative filters. This investigation allows for a better understanding of how watershed characteristics, buffer dimensions, and storm characteristics impact the performance of vegetative filters. Using VFSMOD, relationships that estimate sediment trapping efficiency from the ratio of filter area and field area were developed for different sites. These relationships have been applied for field assessment of concentrated flow.


First-Principles Theory Of The Temperature And Compositional Dependence Of Atomic Short-Range Order In Disordered Cu-Pd Alloys, R. V. Chepulskii, J. B. Staunton, Ezio Bruno, B. Ginatempo, Duane D. Johnson Feb 2002

First-Principles Theory Of The Temperature And Compositional Dependence Of Atomic Short-Range Order In Disordered Cu-Pd Alloys, R. V. Chepulskii, J. B. Staunton, Ezio Bruno, B. Ginatempo, Duane D. Johnson

Duane D. Johnson

We combine the first-principles, Korringa-Kohn-Rostoker coherent potential approximation based calculations of compositional fluctuations with a statistical mechanical ring approximation to study the temperature (T) and composition (c) dependence of the atomic short-range order (SRO) in disordered, face-centred cubic, Cu-Pd alloys. The fourfold splitting of SRO peaks around the equivalent X(0,1,0) points in reciprocal space is obtained in a wide T−c region. Such splitting is shown to be an “energy” effect caused by the absolute minima of the Fourier transform of the effective atomic interactions and related previously to the existence of nested sheets of the disordered alloy’s Fermi surface. However, …


Three-Dimensional Landau Theory For Multivariant Stress-Induced Martensitic Phase Transformations. Ii. Multivariant Phase Transformations And Stress Space Analysis, Valery I. Levitas, Dean L. Preston Jan 2002

Three-Dimensional Landau Theory For Multivariant Stress-Induced Martensitic Phase Transformations. Ii. Multivariant Phase Transformations And Stress Space Analysis, Valery I. Levitas, Dean L. Preston

Valery I. Levitas

In this paper, the three-dimensional Landau model of austenite-martensite transformations constructed in Part I is generalized to include transformations between an arbitrary number of martensitic variants. The model can incorporate all temperature-dependent thermomechanical properties of both phases for arbitrary crystal symmetries, including higher-order elastic constants, and it correctly describes the characteristic features of stress-strain curves for shape-memory alloys and steels, namely, constant transformation strain tensors, constant or weakly temperature dependent stress hysteresis, and transformation at nonzero tangent moduli. Geometric representations of the conditions for phase equilibrium and phase transformations in six-dimensional stress space are developed. For the cubic-tetragonal phase transformation, …


Three-Dimensional Landau Theory For Multivariant Stress-Induced Martensitic Phase Transformations. I. Austenite↔Martensite, Valery I. Levitas, Dean L. Preston Jan 2002

Three-Dimensional Landau Theory For Multivariant Stress-Induced Martensitic Phase Transformations. I. Austenite↔Martensite, Valery I. Levitas, Dean L. Preston

Valery I. Levitas

A three-dimensional Landau theory of stress-induced martensitic phase transformations is presented. It describes transformations between austenite and martensitic variants and transformations between martensitic variants. The Landau free energy incorporates all temperature-dependent thermomechanical properties of both phases. The theory accounts for the principal features of martensitic transformations in shape memory alloys and steels, namely, stress-strain curves with constant transformation strain and constant, or weakly temperature dependent, stress hysteresis, as well as nonzero tangent elastic moduli at the phase transformation point. In part I, the austenite↔martensite phase transformation is treated, while transformations between martensitic variants are considered in part II.


Low-Cost Manufacturing Process For Nanostructured Metals And Alloys, Travis L. Brown, Srinivasan Swaminathan, Srinivasan Chandrasekar, W. Dale Compton, Alexander H. King, Kevin P. Trumble Jan 2002

Low-Cost Manufacturing Process For Nanostructured Metals And Alloys, Travis L. Brown, Srinivasan Swaminathan, Srinivasan Chandrasekar, W. Dale Compton, Alexander H. King, Kevin P. Trumble

Alexander H. King

In spite of their interesting properties, nanostructured materials have found limited uses because of the cost of preparation and the limited range of materials that can be synthesized. It has been shown that most of these limitations can be overcome by subjecting a material to large-scale deformation, as occurs during common machining operations. The chips produced during lathe machining of a variety of pure metals, steels, and other alloys are shown to be nanostructured with grain (crystal) sizes between 100 and 800 nm. The hardness of the chips is found to be significantly greater than that of the bulk material.


Spsj 50th Annual Meeting, Osaka, Japan, May 23-25, 2001, Otto Vogl, Yasuhiko Shirota, Tatsuro Ouchi Jan 2002

Spsj 50th Annual Meeting, Osaka, Japan, May 23-25, 2001, Otto Vogl, Yasuhiko Shirota, Tatsuro Ouchi

Otto Vogl

No abstract provided.